Engine oil is used to lubricate all major engine parts including the crankcase, sump, or oil pan of an internal combustion engine. The incorporation of additive packages typically will improve engine performance by enhancing common base oil (which forms the major component of an engine oil) properties.
These additive packages generally contain detergents, dispersants, anti-acids and friction modifiers. Detergents eliminate build-up of sludge contaminants thus keeping metal surfaces clean and in combination with dispersants will prevent agglomeration of particle impurities on these surfaces. The presence of anti-acids minimise the likelihood of corrosion and damage in engine. In contrast, the inclusion of friction modifiers allows the oil to withstand high pressure conditions. Another component typically present in additive packages is Extreme Pressure (EP) and aids in preventing sliding of metal surfaces from seizing under extreme pressure conditions.